Box joint



Aug. 18, 1925. 1550mm B. A. LANGE BOX JOINT Filed Dec. 24, 1924 gwbentoz Z Patented ug. 18, 19215.

BERTHOLD A. LANGE, 0 F ST. LOUIS, MISSOURI.

BOX Jornr.

application filed December 24, 1924. Serial. N'o. 757,827.

To all whom it may concern:

Be it known that I, BERTHOLD A. LANGE, a citizen of the United States, residing at the city of St. Louis, in the State of Missouri, have invented certain new and useful Improvements inBox Joints, of which the following is a specification. i This invention relates to joints for the edges of boxes formed of pasteboard, fibre board and similar material, and one object of the invention is to provide a novel form of joint or seam which willleave the material with greater tensile strength than the forms of seams hitherto in use.

Another object of the invention is to provide a method and device for enabling'an appreciable width of material for the seam to be upset with a minimum strain on the material in forming the creases.

Divers other objects and advantages will,

be obvious to others skilled in this art after an understanding of this invention ls had,

f and it is preferred to accomplish the objects of this invention by the means and in the manner'substant-ially hereinafter described. In the accompanying drawings forming I part of this specification, in which. like numbers of reference denote like parts wherever they occur,

Figure 1 is a transverse vertical sectional view through the forming means of Figure 2, showing the manner of forming the novel seam of this invention;

Figure 2 is an elevation ofthe same; Figure 3 is an end view of the creased material asrit appears after leaving the deviceof Figure 2,

i it appears when folded;

tivel'y, of a modified form of apparatus for Figure 4 is anend view of the material as .-Fi gures. 5 and 6 are longitudinal and transverse vertical sectional views, respecci'easing the material; 7

Figure 7 is a-fragmentary sectional view of apparatus similar to that shown in either Figures 1 or 5, but with the forming surfaces seam;

Figure 8 1s an end view of the material as it appears after having been creased inthe same as folded;

,"Eigure 10 is a fragmentary sectional view showing another modification of the form- 'ing'gsui'faees of the creasing means.

upon the ends-of theupper or movable die" member 6. The bed 1 presents two surfaces,

'7 and 8 respectively, in stepped relation to- 'one another.

The material4, such as pasteboard and the like, is placed upon the bedl, as indicated by. the "dotted lines, and the upper die 6 is then pressed downwardly by any suitable means, and an extension or flange 9 on the die forces the portion of the pasteboard 4 indicated by dotted lines against the surface 8 and the wall 10 intermediate the surfaces 7 and 8. It will be observed that by this operation but a single pair of creases has been formed, one crease 11 being on'the underside of the material, and the other'crease 12 being on the upperside of the material in staggered relation to the crease 11,. The laminations of the material intermediate the two creases have become separated or sheared from one another.

by the upsetting action of the die, thoseportions of the laminations immediately under the creases 11 and 12 havin a curvature which is concentric with their respective creases and which decreases with their remoteness therefrom. In attempting to bend the material at a seam so formed, that particularcrease which serves as a center for those laminated portions which are placed under tension by the bending will function largely in preference to the other crease as the principal axis about which the bending occurs. Otherwise stated, if the left hand flap 13 of the sheet depicted in Figure '3 is bent upwardly, as shown in Figure 4, the crease 12 serves principally'as the axis about which'thebending occurs, while if the same flap is bent downwardly in the opposite direction, the greater portion of the bending would be localized about the crease 11. It

:iS therefore manifest that there is but one modified to produce a modified form of definite axis about which the material will always bend in any one direction. The seam of this invention is therefore a decided improvement over the old form of seam which may be bent upon any one of three 'alterna tive. axes as will be understood by' those skilledin the prior art. Wherever the flap must be folded upon a definite predetermined line, as in the manufacture of boxes,

the seam of this invention is essential. It

male and female rolls 16 and 17, respec tively, affixed to shafts or spindles18 and 19, ournaled in bearings 20, and having aflixed thereto intermeshing gears 21 and 22.

The shaft 18 may be drivenin any common manner. The gears 21 and 22 are so proportioned that the peripheral speeds of the respective rolls at them points of contact with the pasteboard is the same.

'The smallamount of material upset between the closely adjacent creases 11 and 12 in the seam depicted in Figure 3, however, allows the pasteboard to bend through more than a right angle with only extreme difficulty. While the seam of Figure 3, therefore, is preferable for use where bending atright angles is desired, it is also desirable to have seams which will allow bending with facility through one hundred and eighty degrees, as, for instance, is necessary for two of the corneisin knock-down box construction. To

this end, therefore, the modification ofFig- .ures 7, 8 and 9 has been produced, the seam thereof having but one definite axis upon a which it bends in any one direction, and yet bending easily through a straight angle. This seam is produced in the manner illustrated in Figures 7 and 10, the female forming member 23 having a channel 24' interposed between the stepped surfaces 25 and 26, whereby more material may be drawn into the seam, and so increase the flexibility of the latter. The flange 27 of the male member operates closer to the higher Wall 28 of the channel, whereby the crease 29 on the under side of the material is sharper or more pronounced than the curvature of the remainder of the seam. The channel 24 should be deeper for heavier material, so as to draw the flange 30 were higher. The strain due to pulling on the material is also reduced b reason of the fact that the male flange 2; is operated at an appreciable distance from the flange -30. 'rThe finished seam is illustrated in Figure 8, and allows the material to be bent at right angles on a. single definite axis with one flap 31 having a shoulder 32 bracing the other flap 33 as shown in full lines in Figure 9, or the flap 33 may be bentcompletely over the flap 31 as indicated in dotted lines by reason of the greater flexibility of this seam.

In addition to the advantages above enumerated, the seams of this intention, as determined by actual tests, leave the material with greater tensile strength than is possessed by similar material creased with the common double joint of the prior art.

An alternative form of channel having a rounded bottom is shown in Figure 10, and I is especially suitable for very heavy material. I

Having thus of parts, as it is evident that many minor changes may be made therein without departing from the spirit of this invention or the scope of the following claims.

I claim:

1. In means for creasing pasteboard and similar material, the combination of male and female forming members relatively movable toward one another at right angles to the plane of the material, the female forming member having a relatively wide channel, and the male member a relatively narrow flange operating closer to one side of the channel than the other.

2. In means for creasing pasteboard and similar material, the combination of male and female forming members relatively movable toward one another at ri ht angles to the lane of the material, t e female member aving a pair of surfaces in ste ped relation to one another and separated y a channel, and the male member presenting a flange operating closer to the higher side of the channel than the lower.

In testimony whereof hereunto aflix my signature.

BERTHOLD A. LANGE.

fully described this invention, I hereby reserve the benefit of all. changes in form, arrangement, order, or use. 

